## Task

Given the `root`

node of a binary search tree and two integers `low`

and `high`

, return *the sum of values of all nodes with a value in the inclusive range *

`[low, high]`

.

**Example 1:**

**Input:**

root = [10,5,15,3,7,null,18], low = 7, high = 15

**Output:**

32

**Explanation:**

Nodes 7, 10, and 15 are in the range [7, 15]. 7 + 10 + 15 = 32.

**Example 2:**

**Input:**

root = [10,5,15,3,7,13,18,1,null,6], low = 6, high = 10

**Output:**

23

**Explanation:**

Nodes 6, 7, and 10 are in the range [6, 10]. 6 + 7 + 10 = 23.

**Constraints:**

- The number of nodes in the tree is in the range
`[1, 2 * 10`

^{4}`]`

. `1 <= Node.val <= 10`

^{5}`1 <= low <= high <= 10`

^{5}- All
`Node.val`

are**unique**.

This problem was taken from https://leetcode.com/problems/range-sum-of-bst/

## Solution

## DFS Solution

/** * Definition for a binary tree node. * function TreeNode(val, left, right) { * this.val = (val===undefined ? 0 : val) * this.left = (left===undefined ? null : left) * this.right = (right===undefined ? null : right) * } */ /** * @param {TreeNode} root * @param {number} low * @param {number} high * @return {number} */ var rangeSumBST = function(root, low, high) { if(!root) { return; } console.log(root.val); var queue = [root]; var visited = {}; var result = 0.0; function dfsTraverse(root, low, high) { var childNodes = [root?.left, root?.right]; for(const childNode of childNodes) { if(childNode) { var val = childNode.val; console.log(val); dfsTraverse(childNode, low, high); } } } dfsTraverse(root, low, high); return result; }; function TreeNode(val, left, right) { this.val = (val===undefined ? 0 : val) this.left = (left===undefined ? null : left) this.right = (right===undefined ? null : right) } const treeNode = new TreeNode( 10, new TreeNode( 5, new TreeNode(3), new TreeNode(7) ), new TreeNode( 15, null, new TreeNode(18) ) ) rangeSumBST(treeNode, 7, 15);

## BFS solution

/** * Definition for a binary tree node. * function TreeNode(val, left, right) { * this.val = (val===undefined ? 0 : val) * this.left = (left===undefined ? null : left) * this.right = (right===undefined ? null : right) * } */ /** * @param {TreeNode} root * @param {number} low * @param {number} high * @return {number} */ var rangeSumBST = function(root, low, high) { if(!root) { return 0; } var queue = [root]; var visited = {}; var result = 0.0; if(root.val >= low && root.val <= high) { result = root.val; } var leftPointer = 0; while(leftPointer <= queue.length) { var curentNode = queue[leftPointer]; leftPointer ++; var childNodes = [curentNode?.left, curentNode?.right]; for(const childNode of childNodes) { if(childNode) { console.log(childNode.val) if(childNode.val >= low && childNode.val <= high) { result += childNode.val; } queue.push(childNode); } } } return result; };